The following abbreviations that may be found in the specification and/or the drawing figures are defined as follows:                3GPP third generation partnership project        CIF carrier indicator field        DCI downlink control information        DL downlink, from base station to user equipment        eNB E-UTRAN Node B (evolved Node B)        E-UTRAN evolved UTRAN (LTE)        FDD frequency division duplex        ID identification        LTE long term evolution of UTRAN (E-UTRAN)        PCell primary cell        PDCCH physical downlink control channel        PDSCH physical downlink shared channel        PRACH physical random access channel        Rel release (e.g., Rel-10 is release 10)        RA-RNTI random access—radio network temporary identifier        RAR random access response        RRC radio resource control        RH remote radio head        SCell secondary cell        TA timing advance        TS technical standard        TDD time division duplex        UE user equipment, such as a mobile station, mobile node or mobile terminal        UL uplink, from user equipment to base station        UTRAN universal terrestrial radio access network        
In LTE, uplink transmissions of different UEs to a base station are time aligned within a cell and a given UE obtains certain timing information during a random access procedure with the base station. Certain problems can occur when a UE needs to adjust timing separately for more than one cell.